Originally Posted by
Pilot DAR
Isn't a mast bumping event a very low G, too much rotor disc forward, rather than back situation? I was taught that very low G, or excess forward cyclic could result in mast bumping, can too much aft cyclic also result in mast bumping? In any case, would this be a possible mast bumping event, believing that the whole transmission can be seen departing the fuselage?
I recall that the 206B has a pin down from the transmission case, to restrict that transmission tilting motion in a mast bumping situation. If I recall correctly the 206L had a "Noda-Matic" transmission mounting, which was a little different to the 206B.”
I think you are referring to the transmission pin and “Strike Plate” in the 206 A/B. It was a witness indicator of excessive transmission movement not a restricting device.
the pin extended down into a rectangular hole which was surrounded by a thin plate riveted to the transmission deck. If the pin hit the plate with excessive force it could distort the plate or even shear the rivets. Usually caused by excessive lateral not longitudinal movement of the transmission.